Osculating Spaces

1962 ◽  
Vol 14 ◽  
pp. 669-684
Author(s):  
Peter Scherk
Keyword(s):  
Duality Theorem ◽  
Characteristic Curve ◽  
Independent Interest ◽  
Natural Approach ◽  
Osculating Spaces ◽  
Analytical Tools

In this paper an attempt is made to prove some of the basic theorems on the osculating spaces of a curve under minimum assumptions. The natural approach seems to be the projective one. A duality yields the corresponding results for the characteristic spaces of a family of hyperplanes. A duality theorem for such a family and its characteristic curve also is proved. Finally the results are applied to osculating hyperspheres of curves in a conformai space.The analytical tools are collected in the first three sections. Some of them may be of independent interest.

In situ TEM studies of irradiation effects for materials improvement

1991 ◽  
Vol 49 ◽  
pp. 452-453
Author(s):  
Charles W. Allen
Keyword(s):  
Nuclear Reactor ◽  
Austenitic Stainless Steels ◽  
High Energy ◽  
Point Of View ◽  
In Situ Tem ◽  
Irradiation Effects ◽  
Tem Analysis ◽  
Radiation Induced ◽  
Analytical Tools

Irradiation effects studies employing TEMs as analytical tools have been conducted for almost as many years as materials people have done TEM, motivated largely by materials needs for nuclear reactor development. Such studies have focussed on the behavior both of nuclear fuels and of materials for other reactor components which are subjected to radiation-induced degradation. Especially in the 1950s and 60s, post-irradiation TEM analysis may have been coupled to in situ (in reactor or in pile) experiments (e.g., irradiation-induced creep experiments of austenitic stainless steels). Although necessary from a technological point of view, such experiments are difficult to instrument (measure strain dynamically, e.g.) and control (temperature, e.g.) and require months or even years to perform in a nuclear reactor or in a spallation neutron source. Consequently, methods were sought for simulation of neutroninduced radiation damage of materials, the simulations employing other forms of radiation; in the case of metals and alloys, high energy electrons and high energy ions.

The Role of a Decision Rule in Symptomatic Pulmonary Embolism Patients with a Non-high Probability Ventilation-perfusion Scan

1997 ◽  
Vol 78 (02) ◽  
pp. 794-798 ◽  
Author(s):  
Bowine C Michel ◽  
Philomeen M M Kuijer ◽  
Joseph McDonnell ◽  
Edwin J R van Beek ◽  
Frans F H Rutten ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
Decision Rule ◽  
Predictive Value ◽  
Patient Population ◽  
High Probability ◽  
Characteristic Curve ◽  
Stepwise Logistic Regression ◽  
Pulmonary Angiogram ◽  
Symptomatic Pulmonary Embolism ◽  
Perfusion Scan

Summary Background: In order to improve the use of information contained in the medical history and physical examination in patients with suspected pulmonary embolism and a non-high probability ventilation-perfusion scan, we assessed whether a simple, quantitative decision rule could be derived for the diagnosis or exclusion of pulmonary embolism. Methods: In 140 consecutive symptomatic patients with a non- high probability ventilation-perfusion scan and an interpretable pulmonary angiogram, various clinical and lung scan items were collected prospectively and analyzed by multivariate stepwise logistic regression analysis to identify the most informative combination of items. Results: The prevalence of proven pulmonary embolism in the patient population was 27.1%. A decision rule containing the presence of wheezing, previous deep venous thrombosis, recently developed or worsened cough, body temperature above 37° C and multiple defects on the perfusion scan was constructed. For the rule the area under the Receiver Operating Characteristic curve was larger than that of the prior probability of pulmonary embolism as assessed by the physician at presentation (0.76 versus 0.59; p = 0.0097). At the cut-off point with the maximal positive predictive value 2% of the patients scored positive, at the cut-off point with the maximal negative predictive value pulmonary embolism could be excluded in 16% of the patients. Conclusions: We derived a simple decision rule containing 5 easily interpretable variables for the patient population specified. The optimal use of the rule appears to be in the exclusion of pulmonary embolism. Prospective validation of this rule is indicated to confirm its clinical utility.

Kritik der Politischen Ökonomie im 21. Jahrhundert.

2017 ◽  
Vol 47 (188) ◽  
pp. 453-470 ◽  
Author(s):  
Hans-Peter Büttner
Keyword(s):  
Political Economy ◽  
Critical Theory ◽  
Scientific Community ◽  
New World ◽  
Neoclassical Economics ◽  
Price Theory ◽  
Transformation Problem ◽  
Iron Cage ◽  
Analytical Tools

While the majority of the scientific community holds Marxian Value and Price Theory to be internally inconsistent because of the so-called “transformation problem”, these claims can be sufficiently refuted. The key to the solution of the “transformation problem” is quite simple, so this contribution, because it requires the rejection of simultanism and physicalism, which represent the genuine method of neoclassical economics, a method that is completely incompatible with Marxian Critique of Political Economy. Outside of the iron cage of neoclassical equilibrium economics, Marxian ‘Capital’ can be reconstructed without neoclassical “pathologies” and offers us a whole new world of analytical tools for a critical theory of capitalist societies and its dynamics.

The role of serum periostin in the diagnosis of asthma: A meta-analysis

2020 ◽  
Vol 41 (4) ◽  
pp. 240-247
Author(s):  
Lei Yang ◽  
Qingtao Zhao ◽  
Shuyu Wang
Keyword(s):  
Diagnostic Accuracy ◽  
Meta Analysis ◽  
Characteristic Curve ◽  
False Negative ◽  
Summary Receiver Operating Characteristic ◽  
True Negative ◽  
Negative Results ◽  
Noninvasive Biomarker ◽  
Sensitivity Specificity ◽  
Serum Periostin

Background: Serum periostin has been proposed as a noninvasive biomarker for asthma diagnosis and management. However, its accuracy for the diagnosis of asthma in different populations is not completely clear. Methods: This meta-analysis aimed to evaluate the diagnostic accuracy of periostin level in the clinical determination of asthma. Several medical literature data bases were searched for relevant studies through December 1, 2019. The numbers of patients with true-positive, false-positive, false-negative, and true-negative results for the periostin level were extracted from each individual study. We assessed the risk of bias by using Quality Assessment of Diagnostic Accuracy Studies 2. We used the meta-analysis to produce summary estimates of accuracy. Results: In total, nine studies with 1757 subjects met the inclusion criteria. The pooled estimates of sensitivity, specificity, and diagnostic odds ratios for the detection of asthma were 0.58 (95% confidence interval [CI], 0.38‐0.76), 0.86 (95% CI, 0.74‐0.93), and 8.28 (95% CI, 3.67‐18.68), respectively. The area under the summary receiver operating characteristic curve was 0.82 (95% CI, 0.79‐0.85). And significant publication bias was found in this meta‐analysis (p = 0.39). Conclusion: Serum periostin may be used for the diagnosis of asthma, with moderate diagnostic accuracy.

PENGARUH MOTIVASI KERJA, KOMPETENSI, DAN KOMPENSASI TERHADAP KINERJA KARYAWAN RUMAH SAKIT UMUM DAERAH (RSUD) KABUPATEN KEPULAUAN MENTAWAI

2020 ◽  
Author(s):  
Syofrinal
Keyword(s):  
Linear Regression ◽  
Work Motivation ◽  
Regression Coefficient ◽  
Employee Performance ◽  
Primary Data ◽  
Coefficient Of Determination ◽  
Reliability Test ◽  
Mentawai Islands ◽  
Regression Test ◽  
Analytical Tools

The purpose of this study is to test the Influence of Work Motivation, Competence, and Compensation Against Performance Employees Regional General Hospital (RSUD) Mentawai Islands District. This study is a census. The data used are primary data by taking sample of 79 (seventy nine) respondents. This research uses analytical tools such as validity, reliability test, multiple linear regression test, t test, F test and coefficient of determination (R2). The results of this study illustrate that all variables have an effect on employee performance except the compensation variable. The results can be described by the equation Y = 12.752 + 0.248X1 + 0.396X2 + 0.051 X3, where X1 = Work Motivation, X2 = Competence, and X3 = Compensation. This means that the constant of 12.752 states that factors other than the variables X1, X2, and X3 that affect employee performance of 12,752. Work Motivation coefficient of 0.248 states that if the variable X1 added one unit will add the effect of employee performance of 0.248 with the assumption that the competence and compensation variables are constant. The regression coefficient X2 of 0.396 is that if the variable X2 increases one unit will increase the employee performance by 0.396 with the assumption that the variable of work motivation and compensation is constant. Furthermore, with X3 regression coefficient of 0.051. This means that with other factors considered constant, the effect of compensation is less than that of work motivation and competence.

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